STUDY ON THE PROBABILITY OF A DANGEROUS FAILURE IN SAFETY CRITICAL SYSTEMS OF THE TYPE  2V2

Hristo Hristov; Mariya Hristova

Scientific paper ID 1884 : 2019/3

STUDY ON THE PROBABILITY OF A DANGEROUS FAILURE IN SAFETY CRITICAL SYSTEMS OF THE TYPE 2V2

Hristo Hristov, Mariya Hristova

The concept of a dangerous failure in the safety critical system is defined. A task is set to analyze the probability of a dangerous failure within a widely popular class of safety critical systems known as structures.

In the context of system failures, a comparison is made between computer processing and telecommunication transmission of messages. It is known that impulse errors of the individual discharges are (assumed as) independent and the code distance D between the functional vectors is a means of efficient protection against interference during the linear transmission of information. With the increase in distance D the probability qD to transition to a wrong vector abruptly decreases. In computer processing, this security method does not work. Any failure in a microprocessor device, irrespective of its nature (hardware or software), may generate with equal probability all erroneous output vectors N = 2v, where n is the number of vector discharges. The study is performed with the assumption of this condition. Two groups of failures influence system security: Common-Mode Failure (CMF) and Accidental Non-Identification (ANI). This paper is a part of a more extensive research that covers both groups, and yet it focuses on the second type of causes – accidentally non-identified failures ANI. Formulas are elaborated for assessment of ANI dangerous failures and their probability depending on the length of the vectors.

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критични по безопасност системи поведение на системите след отказ надеждност безопасност опасни откази.Safety Critical Systems system behaviour after failure reliability safety dangerous failures.Hristo Hristov Mariya Hristova

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